Polyolefin-based resin compositions and fabricated products produced therefrom

Abstract

A resin composition is a transparent, low-water-absorption polyolefin-based resin composition containing a sorbitol-based derivative of a particular structure, whose polyolefin-based resin having crystallinity of 0% to 20% shows haze of not more than 10%, total light transmittance of not less than 80%, when measured in accordance with ASTM D1003 using an article 3 mm thick molded therefrom as the test specimen, and shows water absorption of not more than 0.1% after 100-hour immersion in water at 23° C., or whose polyolefin-based resin comprises a cyclic olefin-based polymer comprising a cyclic olefin of a particular structure. Preferable examples of the polyolefin-based resin include the aforesaid cyclic olefin-based polymer and a polycyclohexane-based resin. This resin composition is used for transparent resin moldings that are useful as optical products and moldings for medical and pharmaceutical use because it has excellent transparency, heat resistance, rigidity and water vapor resistance and the decline in its transparency in a high-temperature/high-humidity atmosphere will be little.

What we claim is:  
     
       1. A cyclic olefin-based resin composition comprising: 
       a cyclic olefin-based resin having crystallinity of 0% to 20% which shows haze of not more than 10% and total light transmittance of not less than 80%, when measured in accordance with ASTM D1003 using an article 3 mm thick molded therefrom as the test specimen, and shows water absorption of not more than 0.1% after 100-hour immersion in water at 23° C., and  
       a sorbitol-based derivative which is represented by any of the following general formulas I-a to I-e:                    
        wherein R and R′, each of which may be the same or different, are any of an alkyl group having 1 to 8 carbon atoms, a halogen atom and an alkoxy group having 1 to 4 carbon atoms, and m and n are, each independently of each other, any of integers from 0 to 3;                    
        wherein R 1  and R 8  are either an aliphatic acyl group having 10 to 30 carbon atoms or a hydrogen atom.  
     
     
       2. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the cyclic olefin-based resin comprises at least one of (a) cyclic olefin-based polymer selected from the group consisting of A-1, A-2, A-3 and A-4 and (b) a polycyclohexane-based resin; 
       wherein A-1 an α-olefin-cyclic olefin random copolymer obtained by copolymerizing α-olefin having 2 to 20 carbon atoms and the cyclic olefin represented by the following formula II or III:                    
       wherein, n is 0 to 1, m is integers of 0 or a number not less than 1, q is 0 or 1, R 1  to R 18  and R a  and R b  are, each independently of each other, a hydrogen atom, a halogen atom or a hydrocarbon group, and R 15  to R 18  may be bonded with each other to form a monocyclic or polycyclic ring, while the said monocyclic or polycyclic ring may have a double bond or R 15  and R 16 , or R17 and R 18 , may form an alkylidene group                    
       wherein, p and q are integers of 0 or a number not less than 1, m and n are 0, 1 or 2, R 1  to R 19  are, each independently of each other, a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group an alicyclic hydrocarbon group, an aromatic hydrocarbon group or an alkoxy group, while the carbon atom to which R 9  and R 10  are attached and the carbon atom to which R 13  or R 11  is attached may be bonded directly or via an alkylene group having 1 to 3 carbon atoms and, when n=m=0, R 15  and R 12 , or R 15  and R 19 , may be bonded with each other to form a monocyclic or polycyclic aromatic ring; and 
       A-2 is a ring-opening polymer or copolymer of the cyclic olefin represented by the above formula II or III,  
       A-3 is a hydride of the ring-opening polymer or copolymer of (A-2) above, and  
       A-4 is a graft-modified material of A-1, A-2 or A-3 above.  
     
     
       3. A cyclic olefin-based resin composition which comprises at least one of the cyclic olefin-based polymers selected from the group consisting of the following A-1, A-2, A-3 and A-4 and the sorbitol-based derivative represented by formulas I-a to I-e as defined in  claim 1 : 
       wherein (A-1) is an α-olefin-cyclic olefin random copolymer obtained by copolymerizing α-olefin having 2 to 20 carbon atoms and the cyclic olefin represented by the formula (II) or (III); 
       (A-2) is a ring-opening polymer or copolymer of the cyclic olefin represented by the above formula II or III                    
       A-3 is a hydride of the ring-opening polymer or copolymer of A-2 as defined above; and  
       A-4 is a graft-modified material of A-1, A-2 or A-3 as defined above.  
     
     
       4. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the sorbitol-based derivative is a dibenzylidene sorbitol derivative represented by the formula (I-a) as defined in  claim 1 . 
     
     
       5. A cyclic olefin-based resin composition as claimed in  claim 1 , which contains 0.01 to 10 parts by weight of a sorbitol-based derivative against 100 parts by weight of the cyclic olefin-based resin. 
     
     
       6. A cyclic olefin-based resin composition molding, which is formed from the cyclic olefin-based resin described in  claim 1 . 
     
     
       7. A cyclic olefin-based resin composition molding as claimed in  claim 6 , wherein the molding is an optical product. 
     
     
       8. A cyclic olefin-based resin composition molding as claimed in  claim 6 , wherein the molding is a molding for medical and pharmaceutical use. 
     
     
       9. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the cyclic olefin-based resin has a glass transition temperature (Tg) of at least 70° C. 
     
     
       10. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the cyclic olefin-based resin has a melt flow at 260° C. and a load of 2.16 kg in accordance with ASTM D1238 is about 0.1 to 200 g/10 mins. 
     
     
       11. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the cyclic olefin-based resin has a softening point of at least 30° C. as measured by the thermal mechanical analyzer (TMA). 
     
     
       12. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the sorbitol based derivative is selected from the group consisting of 1,3,2,4-dibenzylidenesorbitol, 1,3-benzylidene-2,4-p-methylbenzylidenesorbitol, 1,3-benzylidene-2,4-p-ethylbenzylidenesorbitol, 1,3-p-methylbenzylidene-2,4-benzylidenesorbitol, 1,3-p-ethylbenzylidene-2,4-benzylidenesorbitol, 1,3-p-methylbenzylidene-2,4-p-ethylbenzylidenesorbitol, 1,3-p-ethylbenzylidene-2,4-p-methylbenzylidenesorbitol, 1,3,2,4-di(p-methylbenzylidene)sorbitol, 1,3,2,4-di(p-ethylbenzylidene)sorbitol, 1,3,2,4-di(p-n-propylbenzylidene)sorbitol, 1,3,2,4-di(p-i-propylbenzylidene)sorbitol 1,3,2,4-di(p-n-butylbenzylidene)sorbitol, 1,3,2,4-di(p-s-butylbenzylidene)sorbitol, 1,3,2,4-di(p-t-butylbenzylidene)sorbitol, 1,3,2,4-di(2′,4′-dimethylbenzylidene)sorbitol, 1,3,2,4-di(p-methoxybenzylidene)sorbitol, 1,3,2,4-di(p-ethoxybenzylidene)sorbitol, 1,3-benzylidene-2,4-p-chlorobenzylidenesorbitol, 1,3-p-chlorobenzylidene-2,4-benzylidenesorbitol, 1,3-p-chlorobenzylidene-2,4-p-methylbenzylidenesorbitol, 1,3-p-chlorobenzylidene-2,4-p-ethylbenzylidenesorbitol, 1,3-p-methylbenzylidene-2,4-p-chlorobenzylidenesorbitol, 1,3-p-ethylbenzylidene-2,4-p-chlorobenzylidenesorbitol and 1,3,2,4-di(p-chlorobenzylidene)sorbitol, and mixtures comprising not less than two of the above. 
     
     
       13. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the sorbitol based derivative is represented by the formula X,                    
       wherein R an R′, each may be the same or different and are a methyl group or an ethyl group. 
     
     
       14. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the sorbitol based derivative is in a blending amount of 0.01 to 10 parts by weight of 100 parts by weight of the cyclic olefin-based derivative. 
     
     
       15. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the sorbitol based derivative is in a blending amount of 0.05 to 5 parts by weight of 100 parts by weight of the cyclic olefin-based derivative. 
     
     
       16. A cyclic olefin-based resin composition as claimed in  claim 1 , wherein the sorbitol based derivative is in a blending amount of 0.05 to 3 parts by weight of 100 parts by weight of the cyclic olefin-based derivative.